This application to the National Library of Medicine is to provide short term assistance for the preparation of an atlas of the human cerebellum in printed book form and on CD-ROM. The goal of this project is to develop a detailed atlas of the human cerebellum that will be accessible to clinicians and investigators around the world whether they are dependent upon computer based information systems or not. The atlas is designed so that it may be incorporated into international databases of the human brain accessible through the world wide web, such as the Visible Human Project of the National Library of Medicine, and the International Consortium for Brain Mapping. The intense interest and growth of information about the organization and function of the human brain has focused to a large extent on the cerebral cortex. The understanding of the function of the cerebellum has advanced considerably in recent years, particularly with respect to its involvement in higher brain functions concerned with thought and emotion. Functional neuroimaging studies in particular have shown cerebellar activation by cognitive tasks, but there are only vague notions of which particular cerebellar structures are being activated by these tasks. This is in large measure a reflection of the fact that there is no useful guide for neuroimaging purposes to the landmarks and structures of the human cerebellum. The work that the Principal Investigator has performed to date, and which he plans to publish with his collaborators with the help of the National Library, will remedy this problem. This project uses very high resolution magnetic resonance images, state of the art computer technology, and a universally accepted stereotaxic (Talairach) coordinate system to analyze the data, and it is combined with a thorough revision and simplification of previously confusing cerebellar nomenclature. The book and CD-ROM proposed in this application present the gross morphology of the human cerebellum with previously unattainable clarity and precision. This 3- dimensional atlas of the human cerebellum in Talairach space has the potential to become the standard anatomic reference in the field of anatomic and functional neuroimaging of the cerebellum.